Individual and age-related variation in chromatic contrast adaptation

Sarah L. Elliott, John S Werner, Michael A. Webster

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

Precortical color channels are tuned primarily to the LvsM (stimulation of L and M cones varied, but S cone stimulation held constant) or SvsLM (stimulation of S cones varied, but L and M cone stimulation held constant) cone-opponent (cardinal) axes, but appear elaborated in the cortex to form higher-order mechanisms tuned to both cardinal and intermediate directions. One source of evidence for these higher-order mechanisms has been the selectivity of color contrast adaptation for noncardinal directions, yet the degree of this selectivity has varied widely across the small sample of observers tested in previous studies. This study explored the possible bases for this variation, and in particular tested whether it reflected agerelated changes in the distribution or tuning of color mechanisms. Observers included 15 younger (18-22 years of age) and 15 older individuals (66-82), who adapted to temporal modulations along one of four chromatic axes (two cardinal and two intermediate axes) and then matched the hue and contrast of test stimuli lying along eight different directions in the equiluminant plane. All observers exhibited aftereffects that were selective for both the cardinal and intermediate directions, although selectivity was weaker for the intermediate axes. The degree of selectivity increased with the magnitude of adaptation for all axes, and thus adaptation strength alone may account for much of the variance in selectivity among observers. Older observers showed a stronger magnitude of adaptation thus, surprisingly, more conspicuous evidence for higher-order mechanisms. For both age groups the aftereffects were well predicted by response changes in chromatic channels with linear spectral sensitivities, and there was no evidence for weakened channel tuning with aging. The results suggest that higher-order mechanisms may become more exposed in observers or conditions in which the strength of adaptation is greater, and that both chromatic contrast adaptation and the cortical color coding it reflects remain largely intact in the aging visual system.

Original languageEnglish (US)
Pages (from-to)1-21
Number of pages21
JournalJournal of Vision
Volume12
Issue number8
DOIs
StatePublished - 2012

Fingerprint

Color
Age Groups
Direction compound

Keywords

  • Color mechanisms
  • Contrast adaptation
  • Human aging

ASJC Scopus subject areas

  • Ophthalmology
  • Sensory Systems

Cite this

Individual and age-related variation in chromatic contrast adaptation. / Elliott, Sarah L.; Werner, John S; Webster, Michael A.

In: Journal of Vision, Vol. 12, No. 8, 2012, p. 1-21.

Research output: Contribution to journalArticle

Elliott, Sarah L. ; Werner, John S ; Webster, Michael A. / Individual and age-related variation in chromatic contrast adaptation. In: Journal of Vision. 2012 ; Vol. 12, No. 8. pp. 1-21.
@article{e50cff4cf64d4a0ab5383f8ca311ec44,
title = "Individual and age-related variation in chromatic contrast adaptation",
abstract = "Precortical color channels are tuned primarily to the LvsM (stimulation of L and M cones varied, but S cone stimulation held constant) or SvsLM (stimulation of S cones varied, but L and M cone stimulation held constant) cone-opponent (cardinal) axes, but appear elaborated in the cortex to form higher-order mechanisms tuned to both cardinal and intermediate directions. One source of evidence for these higher-order mechanisms has been the selectivity of color contrast adaptation for noncardinal directions, yet the degree of this selectivity has varied widely across the small sample of observers tested in previous studies. This study explored the possible bases for this variation, and in particular tested whether it reflected agerelated changes in the distribution or tuning of color mechanisms. Observers included 15 younger (18-22 years of age) and 15 older individuals (66-82), who adapted to temporal modulations along one of four chromatic axes (two cardinal and two intermediate axes) and then matched the hue and contrast of test stimuli lying along eight different directions in the equiluminant plane. All observers exhibited aftereffects that were selective for both the cardinal and intermediate directions, although selectivity was weaker for the intermediate axes. The degree of selectivity increased with the magnitude of adaptation for all axes, and thus adaptation strength alone may account for much of the variance in selectivity among observers. Older observers showed a stronger magnitude of adaptation thus, surprisingly, more conspicuous evidence for higher-order mechanisms. For both age groups the aftereffects were well predicted by response changes in chromatic channels with linear spectral sensitivities, and there was no evidence for weakened channel tuning with aging. The results suggest that higher-order mechanisms may become more exposed in observers or conditions in which the strength of adaptation is greater, and that both chromatic contrast adaptation and the cortical color coding it reflects remain largely intact in the aging visual system.",
keywords = "Color mechanisms, Contrast adaptation, Human aging",
author = "Elliott, {Sarah L.} and Werner, {John S} and Webster, {Michael A.}",
year = "2012",
doi = "10.1167/12.8.11",
language = "English (US)",
volume = "12",
pages = "1--21",
journal = "Journal of Vision",
issn = "1534-7362",
publisher = "Association for Research in Vision and Ophthalmology Inc.",
number = "8",

}

TY - JOUR

T1 - Individual and age-related variation in chromatic contrast adaptation

AU - Elliott, Sarah L.

AU - Werner, John S

AU - Webster, Michael A.

PY - 2012

Y1 - 2012

N2 - Precortical color channels are tuned primarily to the LvsM (stimulation of L and M cones varied, but S cone stimulation held constant) or SvsLM (stimulation of S cones varied, but L and M cone stimulation held constant) cone-opponent (cardinal) axes, but appear elaborated in the cortex to form higher-order mechanisms tuned to both cardinal and intermediate directions. One source of evidence for these higher-order mechanisms has been the selectivity of color contrast adaptation for noncardinal directions, yet the degree of this selectivity has varied widely across the small sample of observers tested in previous studies. This study explored the possible bases for this variation, and in particular tested whether it reflected agerelated changes in the distribution or tuning of color mechanisms. Observers included 15 younger (18-22 years of age) and 15 older individuals (66-82), who adapted to temporal modulations along one of four chromatic axes (two cardinal and two intermediate axes) and then matched the hue and contrast of test stimuli lying along eight different directions in the equiluminant plane. All observers exhibited aftereffects that were selective for both the cardinal and intermediate directions, although selectivity was weaker for the intermediate axes. The degree of selectivity increased with the magnitude of adaptation for all axes, and thus adaptation strength alone may account for much of the variance in selectivity among observers. Older observers showed a stronger magnitude of adaptation thus, surprisingly, more conspicuous evidence for higher-order mechanisms. For both age groups the aftereffects were well predicted by response changes in chromatic channels with linear spectral sensitivities, and there was no evidence for weakened channel tuning with aging. The results suggest that higher-order mechanisms may become more exposed in observers or conditions in which the strength of adaptation is greater, and that both chromatic contrast adaptation and the cortical color coding it reflects remain largely intact in the aging visual system.

AB - Precortical color channels are tuned primarily to the LvsM (stimulation of L and M cones varied, but S cone stimulation held constant) or SvsLM (stimulation of S cones varied, but L and M cone stimulation held constant) cone-opponent (cardinal) axes, but appear elaborated in the cortex to form higher-order mechanisms tuned to both cardinal and intermediate directions. One source of evidence for these higher-order mechanisms has been the selectivity of color contrast adaptation for noncardinal directions, yet the degree of this selectivity has varied widely across the small sample of observers tested in previous studies. This study explored the possible bases for this variation, and in particular tested whether it reflected agerelated changes in the distribution or tuning of color mechanisms. Observers included 15 younger (18-22 years of age) and 15 older individuals (66-82), who adapted to temporal modulations along one of four chromatic axes (two cardinal and two intermediate axes) and then matched the hue and contrast of test stimuli lying along eight different directions in the equiluminant plane. All observers exhibited aftereffects that were selective for both the cardinal and intermediate directions, although selectivity was weaker for the intermediate axes. The degree of selectivity increased with the magnitude of adaptation for all axes, and thus adaptation strength alone may account for much of the variance in selectivity among observers. Older observers showed a stronger magnitude of adaptation thus, surprisingly, more conspicuous evidence for higher-order mechanisms. For both age groups the aftereffects were well predicted by response changes in chromatic channels with linear spectral sensitivities, and there was no evidence for weakened channel tuning with aging. The results suggest that higher-order mechanisms may become more exposed in observers or conditions in which the strength of adaptation is greater, and that both chromatic contrast adaptation and the cortical color coding it reflects remain largely intact in the aging visual system.

KW - Color mechanisms

KW - Contrast adaptation

KW - Human aging

UR - http://www.scopus.com/inward/record.url?scp=84866002858&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84866002858&partnerID=8YFLogxK

U2 - 10.1167/12.8.11

DO - 10.1167/12.8.11

M3 - Article

C2 - 22904356

AN - SCOPUS:84866002858

VL - 12

SP - 1

EP - 21

JO - Journal of Vision

JF - Journal of Vision

SN - 1534-7362

IS - 8

ER -